为了分析雾天多次散射引起的激光透射仪能见度测量误差，结合激光大气透射仪的系统参量，基于平流雾和辐射雾分布模型，采用蒙特卡洛法对激光在雾中的传输特性进行了理论分析和数值模拟，获得了雾天透过率数据，并计算得到了多次散射引起的能见度误差。结果表明，在雾天气下随着空气中含水量的增多，多次散射越明显，透过率测量误差越大，辐射雾的透过率相对误差高达116.76%；同等条件下，当接收机直径为100cm时，辐射雾多次散射引起的能见度测量误差为19.30%；同时选取较小的接收机直径可以减小多次散射引起的能见度测量误差。因此,在雾天应用激光透射仪进行能见度测量时，需考虑多次散射的影响。此研究结果对实际雾天气下激光大气透射仪能见度的测量具有重要的指导意义。

The visibility errors induced by the multiple-scattering effects are further discussed considering the system parameters of the laser transmissometers, which have been regarded as promising visibility meters used in airports around the world. Based on the size distributions of the advection fog and radiation fog, the transmission of photons is simulated numerically using the Monte-Carlo method. It is noted that the multiple-scattering effects would become more serious for larger water content of the fog, which may cause significant visibility errors as the outputs of the transmissometers. The relative error of transmittance of radiation fog is even possible to achieve 116.76%, and the error of visibility caused by multiple scattering of radiation fog is 19.30% when the diameter of receiver is 100cm. The simulation results further reveal that reducing the receiver aperture may sufficiently suppress the multiple-scattering effects. It is necessary to consider the multiple-scattering effects on the visibility measurement especially for the low-visibility atmosphere, e.g., in dense fog and haze, which gives us important hints on the visibility measurement of laser transmissometers in dense fog and haze.